This invention relates to an improved expansion joint system for sealing roadway gaps between adjacent roadway slabs. It also relates to an improved method for installing an expansion joint sealing system and for inserting and replacing a sealing gland or membrane.
The sealing of roadway gaps has become increasingly important and is increasingly required by bridge engineers. Although it has always been important to provide bridge gap spanning devices for purposes of enabling traffic to cross expansion joints, in recent times the advantages and importance of overall bridge deck water-proofing and the sealing of gaps against the passage of water and debris has been recognized, especially in those geographic areas in which deicing chemicals and salts are widely used to assist in providing bare pavements during the winter months. The amount of damage which salts and the like have done to bridges and the tremendous maintenance costs and potential danger to life and property is now becoming fully apparent.
A wide variety of devices has been developed in the past for effecting the sealing of roadway gaps. These range from compression seals disposed in the gaps between slab sections to various kinds of sophisticated and sometimes complex structures which have been suggested for use. Among the expansion joint sealing devices which have been suggested for use are those shown in U.S. Pat. Nos. 3,626,822; 3,331,294; 3,570,378; and 3,981,601. Other sealing devices suggested for use are waterstops of the type shown in U.S. Pat. No. 2,246,903, and devices of the types shown in Koester, Expansion Joints, Transatlantic Arts, Inc., 1969 at pages 22-39 and 296. Systems based on these and related devices have met with varying degrees of success. Yet another type of sealing system is disclosed in U.S. Pat. No. 4,111,583 owned by the present assignee.
The need remains, however, for improved devices of the type generally typified by the sealing system disclosed in U.S. Pat. No. 4,111,583. To that end, the devices of the present invention provide enhanced sealing capability, together with ease of installation, ease of replacement and lesser cost. Devices of the present invention also make it possible to seal an expansion joint without exposing the fastening devices to vehicle and snowplow impacts.